Compute Grid Spacing for a Given Y+

Improve CFD Accuracy with Correct Mesh Resolution

It's important that your mesh near the wall is properly sized to ensure
accurate simulation of the flowfield. This calculator computes the
height of the first mesh cell off the wall required to achieve a desired
Y+ using flat-plate boundary layer theory.

Input

U∞:
freestream velocity (m/s)

ρ:
freestream density (kg/m3)

μ:
dynamic viscosity (kg/m s)

L:
reference length (m)

y+:
desired y+

Output

Δs:
wall spacing (m)

Rex:
Reynolds number

Note: -1 indicates an input error

Calculate Grid Spacing on iPhone and AndroidTM

Now you can compute wall spacing while at your desk or while on
the road with the Y+ Calculator for iPhone or Android.
This free app is a handy
tool for calculating the grid spacing at a wall to achieve a target
y+ value for viscous computational fluid dynamics (CFD) computations.
Simply specify the flow conditions, the desired y+ value, and
compute your grid spacing. The Y+ Calculator converts between SI
and Imperial units.